Sparse Code Multiple Access (SCMA) is a non-orthogonal multiple access scheme that allows multiple devices, or user equipments (UEs), to share channel resources. Potential transmit devices are allocated time and frequency resources, also referred to as resource units. In SCMA, potential transmit devices are also assigned a sparse codebook that allows superposition of device transmissions, which allows SCMA systems to support a greater number of connected devices.
Although communications systems using SCMA offer high bandwidth for larger numbers of connected devices, the ever increasing need for greater bandwidth to support demanding applications (such as high-definition media streaming, faster web browsing, rapid file transfers, and the like) has prompted further study to improve upon the performance afforded by SCMA. Therefore, there is a need to support more connected devices and/or increase the bandwidth available for each connected device.